Summary: Right after Texas was annexed into the states, the US fought a war with Mexico because they wouldn't sell California to us. The war lasted from 1846-1847 with Americans winning the war. The Guadalupe Hidalgo Treaty ended the war and gave the U.S. land that consists of California, New Mexico, Nevada, and Utah. A dispute once again rose on whether they should be free or slave states. This is when the Compromise of 1850 was born. The compromise gave us 5 major points, the points are that California would be a free state, the new states (Utah and New Mexico) would decide by popular sovereignty, the slave trade in DC would be outlawed, the Texas northern border was also set, and last but not least there would be a stricter fugitive slave law.
Northern Perspective: Northerners were quite happy that California joined as a free state because this balanced the Senate. However, the majority of the North strongly disagreed with the fugitive slave law because it basically meant a slave could be in a free state and still be sent back to slavery.
Southern Perspective: Southerners weren’t pleased with California coming in as free soil because slavery was their main source of income. The South was also ready to enforce the fugitive slave act with more strictness.